Experimental Study and Numerical Analysis on Seismic Performance of Splicing Joints Between Modular Steel Structures

To enhance the assembly efficiency and seismic performance of connections in modular steel structures， quasi-static low-cycle reversed loading tests and finite element simulations were employed to investigate the ultimate bearing capacity， failure mechanisms， hysteretic behavior， and energy dissipation of inter-module splicing joints under cyclic loading. The results indicated that： the internal partition plates installed in the column panel zone had a significant effect on the seismic performance of the joints and achieved a notable enhancement of the stiffness of the column walls； the cover plates installed on the upper and lower flanges of the modular beam effectively transferred the beam-end bending moments， promoted the outward relocation and full development of the beam-end plastic hinges， and thus significantly improved the seismic performance of the joints； the L-shaped connectors strongly enhanced the stiffness of the column walls in the joint core area and notably improved both the bearing capacity and ductility of the joints. Furthermore， parametric and stress-path analyses revealed that varying the thickness of horizontal connecting plates had no significant impact on bearing capacity or energy dissipation but notably improved joint ductility.